Condensate entrainment device

ABSTRACT

Apparatus for effecting a transfer of heat wherein a sump collects water condensed on a cooling coil or heat exchanger. A fan or blower member produces a flow of outside air in a substantially uni-directional manner passing over and through a second heat exchanger to enhance the transmission of heat energy to the ambient environment. A water feed device is disposed in the air flow and configured so as to provide a relatively low pressure in a region of the air flow communicating through the device with the water collected in the sump. An air diversion member is used to conduct a portion of the air flow into the water communicating with the low pressure region. This results in percolation of the air through the water and its ultimate ejectment into the air flow through said water feed device. Passage of the air through the water entrains droplets thus producing a discharge of the condensate water into the air flow.

United States Patent 91 Marsteller CONDENSATE ENTRAINMENT DEVICE [75] Inventor: Kenneth E. Marsteller, Willow Grove, Pa.

[73] Assignee: International Telephone and Telegraph Corporation, Nutley, NJ. 22 Filed: Apr. 19, 1973 [21] Appl. No.: 352,759

[52] U.S. Cl. 62/279, 62/285 [51] Int. Cl. F25b 47/00 [58] Field of Search 62/279, 280, 285

[56] References Cited UNITED STATES PATENTS 2,710,510 6/1955 Roseman 62/280 3,045,449 7/1962 Durdlc 62/279 3,159,984 12/1964 Eberhart 62/279 3,200,608 8/1965 Glickman 62/279 3,442,092 5/1969 Pratt 62/279 3,662,557 5/1972 Morgan 62/279 1451 July 30, 1974 Primary E.raminer-William J. Wye

Attorney, Agent, or Firm-John T. OHalloran; Me-

notti J. Lombardi, Jr.; Peter C. Van Der Sluys [5 7] ABSTRACT changer to enhance the transmission of heat energy to l the ambient environment. A water feed device is disposed in the air flow and configured so as to provide a relatively low pressure in a region of the air flow communicating through the device with the water co1- lected in the sump. An air diversion member is used to conduct a portion of the air flow into the water com-v municating with the low pressure region. This results in percolation of the air through the water and its ultimate ejectment into the air flow through said water feed device. Passage of the air through the water entrains droplets thus producing a discharge of the condensate water into the air flow.

14 Claims, 6 Drawing Figures v PAINTED-" CONDENSATE ENTRAINMENT DEVICE BACKGROUND OF THE INVENTION The present invention relates generally to apparatus for effecting a transfer of heat and is particularly directed to a device for the entrainment of liquid droplets in an air stream. While the invention is subject to a wide range of applications, it is especially suited for the disposal of liquid condensate collected in the operation of a unitary or self-contained air conditioning unit. The invention is particularly described in this latter context.

Self-contained air conditioning units or room air conditioners are usually provided with two heat exchangers, one within the area to be cooled and the other exposed to outdoor air or ambient environment. A pair of fans or a single fan with two sets of impellers are used for circulating separate streams of indoor and outdoor air, respectively. These air streams are directed to the heat exchanger in order to enhance the heat transfer efficiency.

As the indoor air stream circulates through the cooling heat exchanger, moisture condenses on the coils and creates a water disposal problem. The units are obviously designed to collect this condensate in a sump or pan toward which the various parts of the apparatus in which water may collect are channeled. This water may be eliminated by such prosaic devices as drain pipes but as is easily appreciated, any outside attachments of this nature add substantially to the cost of installation and maintenance as well'as mar the esthetic features of the equipment (if such can be appropriately applied to air conditioning units).

Prior art devices have employed a slinger" ring attached to the periphery of the fan or blower in the outer compartment to aid in the disposal of condensate. The slinger ring extends or dips into the condensate water in the sump and during rotation of the fan, draws the water into the air stream ultimately impinging onto the outside or ambient environment heat exchanger. A severe limitation of such contrivance bears on its use in cold or freezing weather. Should the condensate water freeze, the slinger ring becomes entrapped stalling the fan motor. In addition to preventing further condensate removal, it may result in burning out or deterioration of the fan motor performance.

Another prior art device principally directed to overcoming the inherent problems of the slinger ring employes a vortex generator disposed in the air stream and in communication with the condensate to produce a discharge of such condensate droplets into the air stream. The vortex generator causes the development of a relatively low pressure in that portion of the device in contact with the water thus lifting it while subjecting it to turbulence into the air stream. This approach is described in US. Pat. No. 3,079,767, which patent is herein incorporated by reference. While achieving its primary purpose in overcoming prior art problems, it is a relatively inefficient device for the entrainment of condensate water, and is subject to blockage by foreign matter collecting at its inlet. The present invention is intended to both overcome prior art problems as well as enhance the efficiency of condensate entrainment.

Another object of the present invention is to provide an improved and more economical condensate entrainment device.

A further object is to provide a device for discharging liquid in response to a circulating air stream.

SUMMARY OF THE INVENTION The present invention in furtherance of the objects set forth contemplates apparatus for effecting a transfer of heat which contains a sump or liquid gathering area for the containment of liquid generated in the operation of the apparatus. Means is provided for producing a flow of fluid in the area of the sump. A liquid feed means having a discharge orifice is disposed in both the flow and the sump liquid providing a relatively low pressure in the region of the fluid about the discharge orifice. To aid in the aspiration of liquid droplets through the liquid feed means, a fluid diversion means is employed to conduct a portion of the fluid into the liquid communicating with the low pressure region. The passage of the fluid through the liquid en trains droplets which are then ejected through the discharge orifice into the fluid flow.

In the context of a typical self-contained air conditioning apparatus, the sump collects water condensed on the inside cooling coils and the liquid feed means ejects, through the vehicle of entrained water droplets, the condensate into the outside air flow. The latter air flow is generated by a fan or blower unit. The fluid diversion device utilizes a vane disposed in the air stream to introduce air under positive pressure into the water communicating with the liquid feed means, thereby producing an increased percolation action and water entrainment.

For a better understanding of the presentinvention together with further objects and advantages thereof, reference is had to the following description taken in connection with the accompanying drawings. The scope of the invention is pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS nate embodiment of a portion of the condensate entrainment device of the present invention.

The drawings are intended to be illustrative of a preferred embodiment of the present invention and are not intended to delimit its scope. Conventional symbols are used throughout the figures and similar parts are identified by the same number throughout the different views.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, there is shown a schematic representation of an outside blower-heat exchanger arrangement of a typical self-contained or unitary air conditioner apparatus. The remaining cooperative components and parts of an air conditioning unit are well known to those of ordinary skill in the art as well as described in the U.S.-patent hereinbefore referenced and need not be further amplified. A centrifugal blower 11 employs an impeller rotor 13 to produce a substantially uni-directional positive pressure flow of air through a discharge orifice'12. The arrows typically represented by arrow 14 indicate the primary air flow or air stream through blower 11. Air stream 14 is discharged through nozzle 12 entering outside or ambient environment ,heat exchanger 18 from which it ultimately exits. The passage of air stream 14 through heat exchanger 18 enhances the conduction of heat from the air conditioning apparatus to ambient.

Water 16 represents the condensate primarily generated from the inside cooling coils of the air conditioner as collected in a sump contiguous with blower 11. Condensate entrainment device 15 is shown as communicating both with water 16 and air stream 14. Condensate entrainment device 15 is primarily configured to have an orifice or discharge tube arrayed in air stream 14 which is connected to a chamber extending into water 16.

FIG. 2 shows in front elevational view the same schematic arrangement as FIG. 1. Condensate entrainment device 15 employs a depending tube 22 to feed the air entrained water 1.6 into discharge air stream 14. Water 16 is substantially contained in sump area 34 due both to the partition or wall 17 of blower 11 and by the action of the positive pressure air stream 14 forcing water 16 out of its path. A vane 24 is also shown as disposed in air stream 14 and communicating with the sump area To understand the Applicant's novel contribution as well as the operation of the invention, reference is had to FIGS. 3, 4 and 5 considered in the context of the structure depicted in FIGS. 1 and 2. FIG. 3 is an enlarged view of that portion of the apparatus in which is deployed condensate entrainment device 15. Depending tube 22 extends through a complementary aperture in wall 17 into air stream 14. A discharge orifice 26 is in a plane inclined with respect to the direction of air stream 14. The plane is inclined outwardly from the center of the air flow so as to produce a relatively low pressure in the neighborhood or region surrounding orifice 26. The angle of inclination a is typically selected as approximately l5 with respect to the axis of air stream 14 but may find wide variation in actual practice to meet exigencies of operation. Tube 22 smoothly intersects with an inclined wall or surface 21 extending downwardly and laterally into sump water 16. Side walls 23 similarly smoothly intersecting with tube 22 extend downwardly and outwardly from wall 17 toward water 16 but are limited in extension to a point at essentially the desired height of water 16. The results in the formation of substantially rectangular apertures in the side walls 23 of the liquid feed means defined by tube 22 and walls 21 and 23, respectively. Wall 21 is indicated as forming an angle p with respect to the vertical and is typically in the neighborhood of 15, although it must be made clear that such angle is not critical to operation of the invention and may find wide variance in actual application. Similarly, side walls 23 form an angle II with respect to the vertical, the value of which is normally selected at 15. In overall aspect,

that portion of condensate entrainment device 15 extending toward the sump' area 34 may be viewed as forming a vertically sectioned truncated pyramidal shape, althoughother shapes may be found effective under the particular circumstances of usage.

In a typical implementation of the Applicants invention, the various members of the condensate entrainment device have the following dimensions: tube 22 is a thin wall member having an internal diameter of approximately /2 inch and extending into air stream 14 approximately 1 /2 inches; wall 21 has a base dimension of approximately 1% inches and extends outwardly from wall 17 approximately 1 inch; the center line of tube 22 is 1% inches above the plane of the sump and apertures 25 have a height of 5 1 inch.

As shown in FIG. 5, fluid diversion means 24 extending into air of fluid stream 14 communicates with water 16 through opening 35 thus permitting the introduction of a portion of air flow 14 into as well as above water 16. As shown in FIG. 4, vane 24 is inclined toward air flow 14 at an included angle 0 which typically has a value of approximately 45. Again, similarly to the angles p and a, This angle may assume wide variance from the typical while remaining consistent with the performance requirements. Air flow 36 derived from ambient air is also permitted entry into an area above water 16 through the apertures 25 contained in side walls 23. Air streams 14 and 36 find exit through orifice 26 in the form of water droplet entrained air stream 27.

It should be noted at this point and as must be obvious, that the condensate entrainment device while described in terms of specific structure andgeometry may employ substantially different shaped members to achieve the same purpose. For example, vane 24 might readily comprise a tubular member extending toward and up into air stream 14 and similarly, the liquid feed portion may be structured of tubular or conical, shaped members. These examples are not intended to in any way limit the range of shapes and sizes which may be used in the practice of the invention to meet specific performance requirements.

Considering operation in a typical manner, air flow 14 produces a pressure drop in the region of orifice 26 due to its inclined face. This is in accordance with well known and understood physical principles and other pressure reducing devices, such as vortex generators, may be utilized for this purpose. At the same time, air flow 14 also impinges upon fluid diverter 24 causing the air to be forced under positive pressure through opening 35 in wall 17.

In response to the, low pressure region which communicates through tube 22 and the chamber formed by walls 21 and 23 with water 16, the air diverted through opening 35 and entering through apertures 25 is aspirated through the thus forrned liquid feed means exiting through orifice 26 into air stream 14. Then, the air stream 14 carried condensate droplets are directed upon the outside heat exchanger coils where evaporation takes place into the atmosphere.

As air 36 enters apertures 25, it passes over the turbulent surface of water 16 and entrains liquid droplets therein. The air entering through opening 35 percolates through water 16 and in addition to increasing turbulence, .it results in theentrainment of an increased amount of water 16 droplets. The combination of these water entrained air streams results in air stream 27 ciency. Of course, apertures may be replaced by any suitable air entry orifices such as through holes in the side walls 23 or front wall 21 or any other structure forming the communicating chamber between air flow 14 and water 16.

FIG. 6 demonstrates an alternative embodiment of that portion of the Applicants invention concerned with the introduction of air under positive pressure from air stream 14. A modified chamber 33 is in communication with water 16. Air stream 14 impinges upon an arcuate vane 31 resulting in the discharge of air through nozzle 32. Nozzle 32 is intended to lend an increased velocity head to air stream 14 thus producing greater turbulence and percolation through water 16. This alternative embodiment is intended to show the variations in design which may be used to further increase the efficiency and capacity of the condensate entrainment device described in this application.

In sum, there has been described a novel condensate entrainment device for use in heat exchange apparatus. The device contains means for producing a flow of air in the neighborhood of a sump containing condensate. A liquid feed means communicating between the air flow and the water provides a low pressure in the neighborhood of its discharge orifice resulting in a drawing up and ejectment of water entrained air into the main air flow. A diverter vane disposed in the air flow introduces a portion of this air into the water in contact with the liquid feed means thereby substantially increasing the amount of water entrained and its turbulence. This results in an improved condensate disposal device having particular utility in unitary air conditioning appara- IUS.

While there has been described what is considered at present to be a preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made and it is,

therefore, intended that the appended claims include within their ambit all changes and modifications as come within the scope of the invention.

1 claim: 1. Apparatus for effecting a transfer of heat, comprismg:

a sump for holding liquid; means for producing a flow of fluid; liquid feed means communicating between said flow and said liquid and having a discharge orifice in a relatively low pressure region of said flow; and fluid diversion means for conducting a portion of said fluid into said liquid communicating with said liquid feed means so that said fluid percolates through said liquid thereby lifting said liquid and enhancing entrainment of said liquid by said fluid which is ejected into said flow through said discharge orifice. 2. The apparatus of claim 1, wherein said apparatus is an air conditioning unit having an internal cooling heat exchanger and an outside condenser heat ex- 4. The apparatus of claim 3, wherein said air flow is substantially uni-directional and said low pressure generating device comprises an inclined fact directed in said flow so as to produce a pressure drop in said region about said face.

5. The apparatus of claim 3, wherein said fluid diversion means includes a vane extending into said air flow conducting a portion of said air through an opening into said water communicating with said liquid feed means.

6. The apparatus of claim 5, wherein said air flow is substantially uni-directional and said low pressure generating device comprises a face inclined outwardly in the direction of said flow thereby producing a pressure drop in said region about said face.

7. The apparatus of claim 6, wherein said vane is angularly disposed into said air flow.

8. The apparatus of claim 7, wherein said vane forms a nozzle extending through said opening for the introduction of a portion of said air into said water.

9. The apparatus of claim 7, wherein said vane comprises a tubular member communicating with said orifree.

10. The apparatus of claim 7, wherein said liquid feed means comprises a tubularmember extending transversely into said air flow and located above said water surface, said tubular member depending from a chamber extending into said water, that portion of said chamber in contact with said water having a greater cross-sectional area than that portion connection with said tubular member.

11. The apparatus of claim 10, wherein said chamber comprises a substantially conical housing.

12. The apparatus of claim 10, wherein said chamber contains apertures therein for aspiration of air contiguous with said water through said liquid feed means.

13. The apparatus of claim 12, wherein said chamber includes an inclined wall smoothly transitioning from said tubular member and extending into said water, side walls smoothly transitioning from said tubular member and extending to a point a predetermined distance above the normal height of said water thereby forming said apertures in said side walls, and an end wall extending vertically from said tube into said water, said end wall having a complementary entrance aperture for accepting said tubular member.

14. The apparatus of claim 13, wherein said tubular member has an inner diameter of approximately /2 inch, is located approximately 1% inches above said sump plane, and extends approximately 1% inches into said fluid flow; said discharge orifice is in a plane inclined at an angle of approximately 15 with said fluid flow; said inclined wall has a base dimension of approximately 1 /2 inches, is inclined at an angle of approximately 30 with said end wall, and said base extends from said end wall a distance of approximately 1 inch; said apertures have a height of approximately A inch above the plane of said sump and said side walls are inclined at an angle of approximately with respect to said sump plane; said vane has a height of approximately [1 inch, extends into said flow approximately /4 inch and forms an angle of approximately 45 with respect to said air flow; and said opening has a complementary height with respect to said vane and extends laterally approximately 5/16 of an inch. 

1. Apparatus for effecting a transfer of heat, comprising: a sump for holding liquid; means for producing a flow of fluid; liquid feed means communicating between said flow and said liquid and having a discharge orifice in a relatively low pressure region of said flow; and fluid diversion means for conducting a portion of said fluid into said liquid communicating with said liquid feed means so that said fluid percolates through said liquid thereby lifting said liquid and enhancing entrainment of said liquid by said fluid which is ejected into said flow through said discharge orifice.
 2. The apparatus of claim 1, wherein said apparatus is an air conditioning unit having an internal cooling heat exchanger and an outside condenser heat exchanger, said liquid is water condensed on said cooling heat exchanger and said fluid is ambient air.
 3. The apparatus of claim 2, wherein said discharge orifice is formed in a low pressure generating device which is disposed in a positive pressure air flow.
 4. The apparatus of claim 3, wherein said air flow is substantially uni-directional and said low pressure generating device comprises an inclined fact directed in said flow so as to produce a pressure drop in said region about said face.
 5. The apparatus of claim 3, wherein said fluid diversion means includes a vane extending into said air flow conducting a portion of said air through an opening into said water communicating with said liquid feed means.
 6. The apparatus of claim 5, wherein said air flow is substantially uni-directional and said low pressure generating device comprises a face inclined outwardly in the direction of said flow thereby producing a pressure drop in said region about said face.
 7. The apparatus of claim 6, wherein said vane is angularly disposed into said air flow.
 8. The apparatus of claim 7, wherein said vane forms a nozzle extending through said opening for the introduction of a portion of said air into said water.
 9. The apparatus of claim 7, wherein said vane comprises a tubular member communicating with said orifice.
 10. The apparatus of claim 7, wherein said liquid feed means comprises a tubular member extending transversely into said air flow and located above said water surface, said tubular member depending from a chamber extending into said water, that portion of said chamber in contact with said water having a greater cross-sectional area than that portion connection with said tubular member.
 11. The apparatus of claim 10, wherein said chamber comprises a substantially conical housing.
 12. The apparatus of claim 10, wherein said chamber contains apertures therein for aspiration of air contiguous with said water through said liquid feed means.
 13. The apparatus of claim 12, whereIn said chamber includes an inclined wall smoothly transitioning from said tubular member and extending into said water, side walls smoothly transitioning from said tubular member and extending to a point a predetermined distance above the normal height of said water thereby forming said apertures in said side walls, and an end wall extending vertically from said tube into said water, said end wall having a complementary entrance aperture for accepting said tubular member.
 14. The apparatus of claim 13, wherein said tubular member has an inner diameter of approximately 1/2 inch, is located approximately 1 5/8 inches above said sump plane, and extends approximately 1 1/2 inches into said fluid flow; said discharge orifice is in a plane inclined at an angle of approximately 15* with said fluid flow; said inclined wall has a base dimension of approximately 1 1/2 inches, is inclined at an angle of approximately 30* with said end wall, and said base extends from said end wall a distance of approximately 1 inch; said apertures have a height of approximately 1/4 inch above the plane of said sump and said side walls are inclined at an angle of approximately 75* with respect to said sump plane; said vane has a height of approximately 1/4 inch, extends into said flow approximately 1/4 inch and forms an angle of approximately 45* with respect to said air flow; and said opening has a complementary height with respect to said vane and extends laterally approximately 5/16 of an inch. 